Piston ring



^ June 17, 1930. l v J, wlLLlAMS 1,764,815

. PIsToN RING Filed Dec. 3, 1927 Z3 A l "-n @mmm C] Ho uw 45 Lring iin the next Patented June 17, 1930 JUDSON WILLIAMS, F PHILADELPHIA, PENNSYLVANIA IPISTON RING' Application led December 3, 1927. Serial No. 237,454.

rIhis invention relates to an improved piston ringand seeks, among other objects, to provide a ring capable of uniformly cony forming to the contour of a cylinder wall ,7 so as to at all times provide an eective seal between the piston and the cylinder.

A further object of the invention is to provide a ring peculiarly .adapted to effect wipin'g of the cylinder wall and accommow date'free drainage of the oil collected therey from `so that oil pumping will be substantially prevented.

And the invention seeks, as a still further object, to provide a ring embodying a novel tensioning element.

fOtherobjects of the invention not specifically mentioned in the foregoing will appear during the course of lthe following description. 2@ In the drawings,

l assembly,

Figure 2 is a view partly in section and partly in elevation showing one of the steps involved in the shaping element employed,

Figure 3 is. a view similar to Figure 2 showing another step inthe shaping of said tensioning element,

Figure L1 is a detail sectional view similar to Figure 3 but showing the shaping of a slightly modified form of tensioning element,

IFigure 5 is a fragmentary sectional view showing the assembly of Figure 1 tion within the upper ring groove of an engine piston, Figure 6 isa fragmentary elevation showing a further modified form of tensioning element, and

' Figure 7 is a fragmentary elevation showing the ring assembly of Figure 1 in the uppermost groove of a piston and the use of the tensioning element .of the present invention in connection with a conventional lower groove In carrying the inventioninto eect I employv upper and lower split resilientc ring members 10 and 11, the outward radial tension of which may be as desired. These ring 5o members are provided with flat upper and Figure'l is a perspective view of the ringY of the tensioning` in posiof the piston.

lower faces and, at their ends, are preferably provided with straight joints. I-Iowever, any other suitable joint may be chosen if preferred.

In conjunction with ythe ring members 10 and 11 I provide a split annular frustoconical tensioning element or ring 12 of cast iron. In practice, a suitable number of blanks 13 are cut or sawed from an ordinary pot casting, when, as shown in Figure 2, a number of said blanks are placed -within a die in superposed registering relation, lying flat one upon the other. In Figures 2 and 3 of the drawings I have shown a die base at 14 and a plunger at 15, the base being provided with a conical cavity to receive the superposed blanks, as just noted, and the plunger being tapered to conform to the inclination of said cavity. As initially cut or sawed from the pot casting, the blanks are fiat as shown in Figure 2.

I-Iaving placed the blanks in the cavity of the die base, the plunger is. then forced downwardly into said cavity for compressing the blanks between the plunger and the die base and causing said blanks to assume a frusto-conical shape. The blanks may be heated beforey being placed in the die and shaped while heated or may be placed in the die, shaped and subsequently heated by heating the entire die. The purpose of heating the blanks is, of course, to ultimately cause the blanks to set in their frusto-conical shape so that the finished tensioning elementsl will permanently possess this shape.

In Figure .4 I have shown a slight variation of the invention wherein I employ a die base 16 having a spherically shaped face 17, in conjunction with which I provide a plunger 18 having 'a spherical face 19 conforming to the curvature-of the face 17. Blanks 2O are placed in the die cavity and compressed between the plunger and base and, as will be perceived, the blanks will thus be given a frusto-conical or ogive shape, the blanks being set as previously described in conjunction with the blanks 13, so that the tensioning elements will permanently possess such shape. The blanks 20 are, of course, cut or sawed from an ordinary pot casting, in the against the bottom .tensioning element 12, the only the passage between the ring ment same manner as described in connection with the blanks 13 and the blanks 20 are, therefore, originally Hat.

he ring assembly of the present invention further includes a split resilient expansion spring 21 and in Figure 5 I have shown the assembly in position in the uppermost ring groove 22 of an engine piston 23, the groove being provided with flat parallel top and bottom walls and having a series of drain pasillustrated, the upper ring `flat against the ring groove, while the low- 11 is disposed to seat Hat wall of said groove, and compressed betweensaid members is the tensioning element 12 while the expansion spring 21 is confined by the inner peripheries of said members. The spring 21 will thus press the ring members outwardly to coact with the cylinder wall and conform to the contour thereof so that said members will constantly provide an effective seal beer ring member 27 having the ring assembly of Figure 1 arranged 'in the uppermost ring groove of the piston. In the next lower ring groove of said piston I have shown the use of the tensioning element 12 of-the present invention in conjunction'with a conventional split resilient piston ring 28. As will be observed, the tensioning element 12 is well adapted for such use and when arrangedbelow a -conventional piston ring, as shown, will yieldably press said ring against the top wall of, the ring groove.. Should it be found desirable to arrange the tensioning element above the piston ring, said element would, of course, yieldably ress the ring against the bottom wall of the groove.

Having thus described the invention, what claim is:

1. The combination with a piston having an annular groove therein, of upper and lower sealing rings engaged, respectively, with the top and bottom walls thereof,l an expanding rin in the oove bearing against the inner wa l thereo and the inner periphtween the piston and cylinder. At the same eries off said rings, and a tensioning ring time, the tensioning element 12 will ieldfrusto-conical in shape extending diagoably press the rlng members apart. ownally between said sealing rings and beariston moves upwardly, the member 10 Y w due to the frictional engagement of-said member with the cylinder, tend to leaveithetop wall of the ring groove so that oil may enter said groove above said member while, as the piston moves downwardly, the ring member 11 will, for a like reason, tend to leave ring groove so that oil may enter beneath this latter member into the groove. Furthermore, since the rin members 10 and 11 will at all times be held apart by the tensioning ever, as the `element 12, the annular oil passage defined between said members will be constantly open to the free flow of oil through said passage past the tensioning element into the ring groove to drain therefrom through the .passages 24 into the piston. The ring will thus provide an effective oil wipe and oil pumping will be reduced to a minimum. Shouldit be found necessary or desirable to increase -thetlow of oil through the passage between the ring members, a lineally waved tensioning element 25, as shown in Figure 6, may be provided. Theelement 25 is of cast iron and is setin the same manner as described in connection with the difference between these elements bein t at the element 25 is lineally waved. ceived, oil escapement passages 26 are defined above and below the tensioning element 25 at spaced points throughout the circumference of said `element so that the oil entering members 1Q 11 may readily flow through the escapepassages 26 to enter the ring groove. In Figure 7 I have shown a piston at and vthe bottom wall of the d ing against the sealing rings and the expanding ring.

sa new article of manufacture, a tensioning element, for pistoni-ings formed of a relatively thin resilient frusto-conical annulus of cast iron to withstand the heatl of operating conditionsf anengine cyliner without losing its resiliency and split at one point only whereby axial pressure on said annulus will be distributed sbstantially uniformly throughout the length thereof, the inner and outer peripheries of said annulus being unbroken except at said,v s lit.

pIn testimony whereofI aix 1n si ature.

JUDSON FII: 8.]

will be per- 

